Add new endpoint to query specialist-finder index

New parallel stack to the existing search endpoint so we don't interfere with existing search functionality.
When doing the testing, we've noticed that certain things are configured only for government_test index but not for the govuk (and hence also our new index) - such as spelling typo suggestions, and organisation expansion.

Should the tests be more explicit about calling this out?

lib/rummager/app.rb

@@ -143,6 +143,27 @@ def json_only
     halt(500, env["sinatra.error"].message)
   end
 
+  # Return results for the Specialist Finder searches
+  #
+  # For details, see docs/search-api.md
+  ["/specialist-documents-search.?:request_format?", "/api/specialist-documents-search.?:request_format?"].each do |path|
+    get path do
+      json_only
+
+      query_params = parse_query_string(request.query_string)
+
+      begin
+        results = SearchConfig.run_specialist_document_search(query_params)
+      rescue BaseParameterParser::ParseError => e
+        status 422
+        return { error: e.error }.to_json
+      end
+
+      headers["Access-Control-Allow-Origin"] = "*"
+      results.to_json
+    end
+  end
+
   # Return results for the GOV.UK site search
   #
   # For details, see docs/search-api.md

lib/search/query_builder.rb

@@ -64,13 +64,26 @@ def query
     end
 
     def filter
+      return specialist_documents_post_filter if content_index_names.include?(SearchConfig.specialist_finder_index_name)
+
       Search::FormatMigrator.new(
         search_params.search_config,
         base_query: QueryComponents::Filter.new(search_params).payload,
       ).call
     end
 
-  private
+    def specialist_documents_post_filter
+      { bool:
+        {
+          minimum_should_match: 1,
+          should: [{
+            bool: { must: QueryComponents::Filter.new(search_params).payload }
+          }],
+        },
+      }
+    end
+
+    private
 
     attr_reader :content_index_names, :metasearch_index
 

lib/search_config.rb

@@ -52,6 +52,11 @@ def run_search(raw_parameters)
       search_params.search_config.run_search_with_params(search_params)
     end
 
+    def run_specialist_document_search(raw_parameters)
+      search_params = parse_parameters(raw_parameters)
+      search_params.search_config.run_specialist_document_search_with_params(search_params)
+    end
+
     def run_batch_search(searches)
       search_params = []
       searches.each do |search|
@@ -106,7 +111,7 @@ def search_server
       SearchConfig.index_names,
       SearchConfig.govuk_index_name,
       SearchConfig.content_index_names,
-      self,
+      self
     )
   end
 
@@ -121,6 +126,10 @@ def run_search_with_params(search_params)
     searcher.run(search_params)
   end
 
+  def run_specialist_document_search_with_params(search_params)
+    specialist_document_searcher.run(search_params)
+  end
+
   def run_batch_search_with_params(search_params)
     batch_searcher.run(search_params)
   end
@@ -149,6 +158,10 @@ def new_content_index
     @new_content_index ||= search_server.index_for_search([SearchConfig.govuk_index_name])
   end
 
+  def specialist_documents_content_index
+    @specialist_documents_content_index ||= search_server.index_for_search(SearchConfig.content_index_names + [SearchConfig.specialist_finder_index_name])
+  end
+
   def base_uri
     cluster.uri
   end
@@ -177,6 +190,15 @@ def searcher
     )
   end
 
+  def specialist_document_searcher
+    @specialist_document_searcher ||= Search::Query.new(
+      content_index: specialist_documents_content_index,
+      registries:,
+      metasearch_index:,
+      spelling_index:,
+    )
+  end
+
   def batch_searcher
     @batch_searcher ||= Search::BatchQuery.new(
       content_index:,

lib/search_server.rb

@@ -12,6 +12,7 @@ def initialize(base_uri, schema, index_names, govuk_index_name, content_index_na
       @govuk_index_name = govuk_index_name
       @content_index_names = content_index_names
       @search_config = search_config
+      @specialist_finder_index_name = SearchConfig.specialist_finder_index_name
     end
 
     def index_group(prefix)
@@ -52,7 +53,7 @@ def validate_index_name!(index_name)
 
     def index_name_valid?(index_name)
       index_name.split(",").all? do |name|
-        @index_names.include?(name) || @govuk_index_name == name
+        @index_names.include?(name) || @govuk_index_name == name || @specialist_finder_index_name == name
       end
     end
   end